1. Field of the Invention
The present invention relates generally to rupture disk failure indicating apparatus, and more particularly, but not by way of limitation, to apparatus for indicating a pressure change resulting from the loss in integrity of a rupture disk.
2. Description of the Prior Art
Rupture disks and rupture disk assemblies are often utilized in applications where an indication of the failure of the rupture disks is desirable or necessary. For example, when a rupture disk in process equipment fails and relieves pressurized fluid, it is generally necessary to immediately shut down at least a portion of the equipment or to take other action, and accordingly, an indication of the failure of the rupture disk is highly desirable.
Rupture disks are often sealingly supported internally between annular supporting members which are bolted or clamped together, or which are clamped between bolted flanges. The supporting members and/or bolted flanges are in turn sealingly connected between pressurized fluid containing zones, and consequently, the rupture of a rupture disk usually can not be visually observed and often goes undetected for at least an initial period of time.
In some applications, several rupture disks are positioned in series between pressure zones. Also, rupture disks are very commonly positioned between pressure vessels or system containing pressurized fluid and relief valves connected to the vessels or systems to prevent leakage through the relief valves. A problem commonly experienced in the use of a multiple disk or rupture disk-relief valve combination is that the upstream rupture disk can prematurely fail in a manner whereby fluid pressure is exerted on the downstream rupture disk or the relief valve without being detected. This in turn frustrates the benefits of the combination and can result in the occurrence of a dangerous over-pressure condition.
By the present invention, improved rupture disk failure indicating apparatus for indicating the presence of pressurized fluid resulting from the failure of a rupture disk are provided which can conveniently be utilized in any of the applications described above. As used herein in relation to rupture disks, the term "failure" includes any loss in integrity of a rupture disk whereby pressurized fluid leaks or otherwise passes through the rupture disk.